1. Field of the Invention
The present invention generally relates to the processing of printed machine instructions and, more particularly, systems and apparatus for creating, reproducing, disseminating and storing machine instructions in the form of an encoded symbol.
2. Description of the Prior Art
Currently, more and more emphasis is being placed on the dissemination of information and the accuracy of such information. While a vast amount of data and information is disseminated by electronic networks, such as computer networks, a great deal of information is still distributed in printed form. Only printed information in hard copy form that can be readily saved and reproduced for future reference, is truly capable of providing lasting comfort to a large percent of the population. Unfortunately, the dissemination of printed material is cumbersome, slow and unreliable as compared to the electronic transfer of information and data, and further, once information is in printed form it is difficult to return the information and data to electronic form. Thus, in circumstances where the information being communicated includes instructions on the reproduction, distribution and handling of printed matter it is incumbent on the originator of the instructions to provide job instructions which are not subject to "interpretation" or undesired revision. A facsimile copy of a document destined for a customer should not be erroneously faxed to a competitor, nor should a copy operator make one thousand copies of a manual on the wrong size paper.
One commonly used approach for representing information in a highly convenient machine readable form is to encode the information into a pattern of indicia having elements of different reflectivity, such as the ubiquitous UPC bar code symbol. The bar code symbol is optically scanned and the resulting signals are decoded into data representing the symbol encoding. This data can then be readily entered into and processed by a data processing system. Typical bar code symbols, such as the UPC symbol, are one-dimensional in character and thus are extremely limited in amount of data that can be encoded therein.
Prior art patents, such as U.S. Pat. Nos. 4,757,348 to Rourke et al., 4,716,438 to Farrel, and 4,248,528 to Sahay, have described photocopiers having integrated bar code readers for scanning control sheets fed through a document feeder. The control sheets include copying instructions which were are presented to the copying machine as either an encoded one-dimensional bar code job number on the margin of the document, or a hand-filled job sheet processed by a scanner below the platen of the copier. The job sheets are placed between jobs which are stacked together to avoid stopping and reprogramming each job after the end of a prior job. These systems provided "batch" job capabilities. The prior art bar coded sheets employed one-dimensional bar codes which referenced a job number. The job number referred the controller of the printer to a pre-stored job program stored in the copier's memory. The operator was first required to program the job or job exception into the copying machine through the machine controller such as a standard control panel on the copier where the job program was stored. To enable the particular job that the operator programmed to be matched to a specific document batch, a specific job identifier (e.g., job number) is input to the machine by the operator of the job. A job sheet including the job identifier is then placed, i.e., interleaved, at the beginning of the documents to be processed. Thus, as provided in the '438 patent (col. 6, lines 4-34), and the '348 patent (col. 6, lines 23-53), the job sheet functions as a job identifier for a job which was previously programmed and stored on the copying machine.
The '528 patent describes a job sheet having job instructions to be submitted into a copier feeder. The job sheet included a number of fill-in areas which an operator filled in and placed at the beginning of a set of documents to be processed.
In the above-cited issued patent, U.S. Pat. No. 5,304,786, a two-dimensional bar code symbol is disclosed, which has high information density and capacity capabilities, as well as error detection and correction features. This symbol, known as the PDF417 symbol, is capable of representing as many as 500 characters per square inch of ASCII data. Thus, a relatively small number of PDF417 symbols, and in some cases a single PDF 417 symbol, has the capacity to encode alphanumeric text and control data filling a letter-size document.